The 50 greatest undrafted New England Patriots players in the Bill Belichick era

The New England Patriots' run of Super Bowl success since Bill Belichick took over in 2000 is known for being built on the backbone of Tom Brady and a number of key stars like Tedy Bruschi, Randy Moss and Rob Gronkowski.

But building a great roster top-to-bottom goes far beyond just getting a few key guys. It involves building a great team top-to-bottom, often using guys who were overlooked elsewhere in the league.

Heading into his 19th season, Belichick has proven he's among the best at finding diamonds in the rough in the NFL -- especially those who went undrafted. From Adam Vinatieri to Malcolm Butler, the Patriots have a long history of taking undrafted players and having them thrive in key roles.

Here's a breakdown of the 50 greatest Patriots in Patriots history who did not hear their names called on draft day.

Alexander is indicative of a what the Patriots do with a lot of undrafted players. He was an undersized linebacker who ended up playing mostly special teams. Not a huge, role but still a factor. He played in 45 total games and was in on 51 total tackles as a linebacker and special teamer.

AP Photo

49. CB Sterling Moore

College: SMUPlayed for Patriots: 2011-2012Games Played: 14Stats: 2 interceptions, one for a touchdown

While many undrafted players tend to be restricted to statuses as role players, they do have a tendency of coming out of nowhere to make big plays. That's what happened when Moore emerged as a fill-in defensive back during the Patriots' 2011 playoff run.

The highlight of his run in New England came in the 2011 AFC Championship Game against the Baltimore Ravens. With a chance to pull ahead in the closing seconds, Ravens QB Joe Flacco targeted receiver Lee Evans in the endzone -- with Moore in coverage. Whether it was a breakup by Moore or a stone-cold drop by Evans, the pass fell incomplete.

That opened the door for Ravens kicker Billy Cundiff to miss a chip-shot field goal, and for the Patriots to advance to Super Bowl XLVI.

Another undrafted player known for making a big impact in one game before vanishing, Gray picked up steam for the Patriots in 2014, his third NFL season. Then, he exploded for 37 carries, 201 yards and four touchdowns against the Colts in a 42-20 blowout.

Gray followed that up by famously oversleeping and showing up late to practice, drawing the ire of the coaching staff. Over the rest of the season, Gray saw just 20 carries, and was off the team by the 2015 season.